Thomas,
We don't currently plan to have a "Post to Facebook" button from the admin area. The main reason is because, from the admin area, there's no way to know the 'final' URL of whatever you're posting. The Post button works on the front-end for any page of your site, regardless of the component that creates it. In the admin area, we'd have to know a lot of details about each component to understand how whatever page you're looking at would be rendered on the front-end.
With that said, we do plan a system for auto-posting new content. When enabled, that could automatically post your content to any of the social networks supported when a new Joomla article, K2 item or other supported content is created. That won't be until the 6.2 release, later this summer.
Finally, the social posting functionality requires that the owner of the social channel (FB Page or Group, Twitter Stream, etc) logs into the front-end of your site to grant the proper permissions. So, you'll need some method to let the admin login, at least to set things up. What I'd recommend is that you:
* Disable registrations on your site
* Setup a login area on a 'secret' page of your site. You can do this with a hidden menu item.
It's possible a user or bot may still find the login page, but it wouldn't be usable to anyone other than your admins.
I hope that helps explain, but if you have any questions, just let me know.
Thanks,
Alex
Post to Facebook from backend...
